Perhaps he was given 11 days of Privilege Leave (the same as in April) plus another 48 hours to give 13 days. The UJ (or something) might qualify the 48 hours pass - perhaps it's an "S" and means "unspecified", or is in fact a "J" denoting "unjustified", meaning not backed up by any supporting documentation. It could even be UT, using the form of capital T often written at the time.
Pure guesswork!
Chris